Technological progress is achieved through miniaturization and ultimately we may have machines that are the size of molecules. To power these nano-machines we obviously need molecular-size motors as well. Because such motors must operate under very different conditions than real-life engines, their design must be radically different as well. Excellent examples of molecular motors can be found in our cells, where special motor-proteins perform all kinds of work to keep the cell alive. In this project, we will investigate a biological nano-motor called ATPase that converts chemical energy into torque. Because this motor is so small and its components move so fast, experiments are very difficult. Therefore, we will use computer simulations instead to reveal the action of this molecular motor in atomic details. With new insights obtained from these simulations, we will also design and test artificial nano-motors that operate based on the same principles as the ATPase protein.